Conventional communication devices are specialized for network-related processing. Therefore, they do not include functions for executing general computation (e.g., modification of data and control of data flow). On the other hand, several concepts proposed recently indicate that virtual machines can operate in communication devices to perform general computation within the communication device.
In such cases, the communication device, where virtual machines are installed may execute computation processing. By the environment isolation feature provided by the virtual computing environment, different computation processing can be executed without affecting each another. The virtual computing environment is implemented with software and provides an environment separated from the physical calculation resources. However, problems occur when some applications that need to access information typical to physical environments. For example, consider system software that monitors wireless communication status and performs communication control based on the detected state. For operation of the system software, wireless information such as received power and the number of radio wave interference events detected by the wireless interface is necessary. However, in a virtualized computing environment, the wireless interface is also virtualized. A frame received using wireless communication is converted to a frame in wired communication format before processing. During the conversion process, information included in a header of the received frame and information that is detectable only through the physical wireless interface is lost. Therefore, it is difficult to execute system software for performing the communication control that utilizes the state of wireless communication in the virtual computing environment.
One solution for this problem is the emulation of the wireless interface solely by software. Another method is to allow direct access to the wireless interface, which belongs to the physical resource. Information loss can be prevented by these methods. However, the first method contradicts with the concept of virtualization. Since the specification of wireless interface varies depending on the design, implementation of software would become complicated. One example of the second method that enables direct access to the wireless interface, is SR-IOV specified by PCI-SIG. In this method, it is possible to access information of a wireless LAN from the virtual environment. However, complicated control is needed in the communication device.